Location Of Makkah
Makkah is at the intersection of latitude 21 to 25 degree north and longitude 39 to 49 degree east. It is set in a rugged landscape consisting mostly of solid granite, with rocks sometimes reaching 300 meters (1,000 feet) above see level.
Makkah is enclosed by the Valley of Abraham, which is surrounded by two nearby mountain ranges to the east, west and south. The northern range comprises the Al-Falaq and Qu'aqi'an mountains, while the southern range consists of Abu Hudaidah mountain to the west, Kuday to the south and Abu Qubais and Khindimah to the south-east.
There are three main entrances to Makkah: Al-Mu'allat (also known as Al-Hujûn), Al-Musfalah and Al-Shubaikah.
It is generally agreed that Al-Mu'allat includes all areas which are higher than the Haram and Al-Musfalah covers all areas that are lowers.
Ka'bah & Makkah In History
Edward Gibbon writes about the Ka'bah and its existence before the Christian era in his book:
..... of blind mythology of barbarians - of the local deities, of the stars, the air, and the earth, of their sex or titles, their attributes or subordination. Each tribe, each family, each independent warrier, created and changed the rites and the object of this fantastic worship; but the nation, in every age, has bowed to the religion as well as to the language of Mecca. The genuine antiquity of Caaba ascends beyond the Christian era: in describing the coast of the Red sea the Greek historian Diodorus has remarked, between the Thamudites and the Sabeans, a famous temple, whose superior sanctity was revered by all the Arabians; the linen of silken veil, which is annually renewed by the Turkish emperor, was first offered by the Homerites, who reigned seven hundred years before the time of Mohammad.
Diodorus Siculus was a Greek historian of 1st century BC who wrote Bibliotheca Historica, a book describing various parts of the discovered world. The following lines are the English translation of Greek quoted by Gibbon from the book of Diodorus Siculus (Diodorus of Sicily) describing the 'temple' considered to be the the holiest in the whole of Arabia.
And a temple has been set-up there, which is very holy and exceedingly revered by all Arabians.
It is interesting to know that Claudius Ptolemy of Alexandria, mathematician and astronomer, flourishing about a century after Pliny, undertook to make an atlas of the habitable world. He was not a descriptive geographer, and his book was intended to be no more than a commentary on his maps. He enumerated some hundred and fourteen cities or villages in Arabia Felix.
For example, Dumaetha, placed by Ptolemy just outside the northern boundary of Arabia Felix, must be the mediaeval Arabian Daumet, which is today the chief village of the great oasis of Jauf. Hejr, famous in the "times of ignorance" as the seat of a kingdom, and now Medayin Salih, is Ptolemy's Egra. His Thaim is Teima, now known for its inscriptions to have had temples and some sort of civilization as far back as 500 BC. It is the Tema of Job. In Lathrippa, placed inland from Iambia (Yambo), we recognize the Iathrippa of Stephan of Byzantium, the Yathrib of the early Arab traditions, now honoured as El Medina, the City of Cities.
Apart from this a place called Macoraba is also shown which is identified as Mecca (please refer to the map facing page 17 of reference ). G E von Grunebaum says:
Mecca is mentioned by Ptolemy, and the name he gives it allows us to identify it as a South Arabian foundation created around a sanctuary.
Makkah In The Scriptures
The Qur'ân talks about Bakkah (the older name of Makkah) being the first house of worship appointed for mankind. It also addresses this place as Umm ul-Qurâ i.e., Mother of the Settlements.
Verily, the first House (of worship) appointed for mankind was that at Bakkah (Makkah), full of blessing, and a guidance for Al-'Alamin (the mankind and jinns). In it are manifest signs (for example), the Maqam (place) of Ibrahim (Abraham); whosoever enters it, he attains security. And Hajj (pilgrimage to Makkah) to the House (Ka'bah) is a duty that mankind owes to Allah, those who can afford the expenses (for one's conveyance, provision and residence); and whoever disbelieves [i.e. denies Hajj (pilgrimage to Makkah), then he is a disbeliever of Allah], then Allah stands not in need of any of the 'Alamin (mankind and jinns). [Qur'ân 3:96-97]
The Bible also mentions about the valley of Baca in connection with the pilgrimage. Below is the quote from Psalms 84 (NIV):
1 How lovely is your dwelling place, O LORD Almighty!
2 My soul yearns, even faints, for the courts of the LORD; my heart and my flesh cry out for the living God.
3 Even the sparrow has found a home, and the swallow a nest for herself, where she may have her young-- a place near your altar, O LORD Almighty, my King and my God.
4 Blessed are those who dwell in your house; they are ever praising you.
5 Blessed are those whose strength is in you, who have set their hearts on pilgrimage.
6 As they pass through the Valley of Baca, they make it a place of springs; the autumn rains also cover it with pools.
7 They go from strength to strength, till each appears before God in Zion.
8 Hear my prayer, O LORD God Almighty; listen to me, O God of Jacob.
9 Look upon our shield, O God; look with favor on your anointed one.
10 Better is one day in your courts than a thousand elsewhere; I would rather be a doorkeeper in the house of my God than dwell in the tents of the wicked.
11 For the LORD God is a sun and shield; the LORD bestows favor and honor; no good thing does he withhold from those whose walk is blameless.
12 O LORD Almighty, blessed is the man who trusts in you.
The interpretation of the valley of Baca in the The Jewish Encylopedia is quite interesting, though it does not provide a complete evidence and leaves the reader with a suggestion. Below is the full quote.
Baca, The Valley Of: A valley mentioned in Psalms LXXXIV:7. Since it is there said that pilgrims transform the valley into a land of wells, an old translators gave to Baca, the meaning of a "valley of weeping"; but it signifies rather any valley lacking water. Support for this latter view is to be found in II Samuel V:23 et seq.; I Chronicles XIV:14 et seq., in which the plural form of the same word designates a tree similar to the balsam tree; and it was supposed that a dry valley could be named after this tree. Konig takes Baca from the Arabian Baka'a, and translates it "lack of streams". The Psalmist apparently has in mind a particular valley whose natural condition led him to adopt its name.
The translation of Arabian Baka'a as "lack of stream" seems to throw some light on the nature of the valley before the appearance of the stream ofZam-Zam near Ka'bah which was a dry place with no vegetation whatsoever.
The Anchor Bible Dictionary does not throw any light on it, albeit, there are some suggestions in it too like the The Jewish Encylopedia. Below is the full quote.
Baca, The Valley Of (PLACE): [Hebrew 'emeq habakka'], The valley of Baca (Psalms 84:1) is either a historical place name or a symbolical expression for "deep sorrow". The first part of Psalms 84:6 seems to mean that by "passing through the experience of deep sorrow, righteous ones can make it the source of life." The Septuagint translated the phrase into Greek as "the valley of weeping". The word 'emeq "valley" has the root meaning of "deep", so the expression may mean "deep sorrow".
However, some have considered it as the "valley of the balsam tree" from the same word in plural form found in 2 Samuel 5:24. This is based on the assumption that baka may be a "gum-exuding [weeping] tree". Another possibility is that the word beka'im (plural of baka) may mean "weeping wall-rocks" in the valley of Rephaim on whose tops David and his troops were waiting for the coming of the Philistine army passing through the valley below (2 Samuel 5:24). It seems safe to seek the meaning of baka in relation to the dripping water, since we often find this word in the names related to rivers and wadis, such as Wadi al-Baka in the Sinaitic district and Baca on the wadi in the central Galilee area, W of Meroth. It is also possible to understand beka'im as the place of "weepings" of the Philistine army for their defeat by David. After all these considerations, the expression of "valley of baka" can best be taken as a symbolic expression "weeping" or "deep sorrow" which fits well in the context of Psalms 84:6.
The interpretation of the valley of Baca as a "the valley of weeping" makes sense because of the distress which Hagar(P) underwent when she was left with Ishmael(P) in the barren desert with no means of living.
The two interpretations of Baca, viz., "lack of stream" and "the valley of weeping" appears to fit in the context of pilgrimage to Bakkah, the older name of Makkah where the Ka'bah is situated. Ka'bah has been a place of reverence by all Arabians before the Christian era as we have seen earlier.
And Allah knows best!
 Edward Gibbon (Introduction by Christopher Dawson), Gibbon's Decline And Fall Of The Roman Empire, Volume V, Everyman's Library, London, pp. 223-224.
 Translated by C H Oldfather, Diodorus Of Sicily, Volume II, William Heinemann Ltd., London & Harvard University Press, Cambridge, Massachusetts, MCMXXXV, p. 217.
 D G Hogarth, The Penetration Of Arabia, Alston Rivers Limited, London, 1905, p. 18.
 G E Von Grunebaum, Classical Islam: A History 600-1258, George Allen & Unwin Limited, 1970, p. 19.
 The Jewish Encylopedia, Volume II, Funk & Wagnalls Company, MDCCCCII, p. 415.
 David Noel Freedman (Editor-in-Chief), The Anchor Bible Dictionary, Volume I, Doubleday, p. 566.